An Assessment of the Summer Sport Fishery for Walleye and Northern Pike at Pigeon Lake, 2003 CCONSERVATIONONSERVATION RREPORTEPORT SSERIESERIES The Alberta Conservation Association is a Delegated Administrative Organization under Alberta’s Wildlife Act. CCONSERVATIONONSERVATION RREPORTEPORT SSERIESERIES 25% Post Consumer Fibre When separated, both the binding and paper in this document are recyclable An Assessment of the Summer Sport Fishery for Walleye and Northern Pike at Pigeon Lake, 2003 Bill Patterson Alberta Conservation Association, 111, 4999 – 98 Ave, Twin Atria Building Edmonton, Alberta, Canada T6B 2X3 Report Series Co-editors PETER K.M AKU GARRY J. SCRIMGEOUR Alberta Conservation Association Alberta Conservation Twin Atria Building P.O. Box 40027 #111, 4999 – 98 Avenue Baker Centre Postal Outlet Edmonton, AB, T6B 2X3 Edmonton, AB, T5J 4M9 Conservation Report Series Types: Data, Technical ISBN printed: 0-7785-4786-8 ISBN online: 0-7785-4787-6 ISSN printed: ISSN online: Publication Number: T/ 110 Disclaimer: This document is an independent report prepared by the Alberta Conservation Association. The authors are solely responsible for the interpretations of data and statements made within this report. Reproduction and Availability: This report and its contents may be reproduced in whole, or in part, provided that this title page is included with such reproduction and/or appropriate acknowledgements are provided to the authors and sponsors of this project. Suggested citation: Patterson, B. 2004. An Assessment of the summer sport fishery for walleye and northern pike at Pigeon Lake, 2003. Data Report (D-2004-015), produced by Alberta Conservation Association, Edmonton, Alberta, Canada. 26 pp + App. Cover photo credit: David Fairless Digital copies of conservation reports can be obtained from: Alberta Conservation Association P.O. Box 40027, Baker Centre Postal Outlet Edmonton, AB, T5J 4M9 Toll Free: 1-877-969-9091 Tel: (780) 427-5192 Fax: (780) 422-6441 Email: [email protected] Website: www.ab-conservation.com i EXECUTIVE SUMMARY To recover or maintain Alberta's walleye and pike fisheries, Alberta Natural Resources Service implemented new management strategies in 1996 for walleye and in 1999 for pike. Walleye in Pigeon Lake were likely extirpated by the 1960’s. To restore this important fishery 18.4 million walleye fry and fingerlings were stocked into Pigeon Lake between 1994 and 1999. Consequently, in 1996 the walleye fishery at Pigeon Lake was classified as a stocked lake and a zero daily limit (catch and release regulation) was implemented. In 1999, based on a new northern pike management strategy, the pike fishery at Pigeon Lake was classified as stable-recreational (vulnerable) and a 63 cm (maximum total length, TL) size limit, 3 fish daily limit was implemented. In 1999 a creel survey was conducted at Pigeon Lake to quantify sport angling effort directed at the re-established walleye fishery and to assess the pike stock. Results from these efforts showed that angling pressure and the associated yield of walleye and pike were low. Based on criteria listed in the pike management strategy, the results of the 1999 creel survey indicated the pike stock was likely collapsed. In this report we describe the results of a creel survey conducted from 23 May to 1 September 2003 and compare these data with those collected using similar methods in Pigeon Lake in 1999. Results from these efforts indicated that 7,646 anglers fished Pigeon Lake for 31,517 hours or 3.3 hours/hectare (h/ha) during the 3-month period in 2003. In contrast, angling pressure in 1999 was 1.2 h/ha. Comparisons of the incidental yield between 1999 and 2003 also differed substantially; incidental yield in 2003 (1.0 kilograms/hectare, kg/ha) was about 4-fold higher than that in 1999 (0.023 kg/ha). Similarly, the sport yield of pike (harvest + incidental mortality) in 2003 (0.047 kg/ha) was about 25% higher than that in 1999 (0.035 kg/ha). There was no walleye or pike recruitment observed during the survey period and the usage of the stocked walleye population has increased greatly since 1999. The pike stock in Pigeon Lake appears to be on the verge of collapse. Observed and estimated catch rates were extremely low. Older and larger pike made up the catch and there was no evidence of recruitment. Anglers had low success in catching legal-size pike and there was a high level of inequality in the distribution of catch. ii ACKNOWLEDGMENTS I thank Michelle Wells and Jared Williams, the seasonal crewmembers who interviewed scores of anglers, spent many long and potentially hazardous hours boating on Pigeon Lake and managed the creel and biological data in away that ensured its safety and integrity. I would also like to thank Alberta Fish and Wildlife and Alberta Parks for collaborating on this project, the use of their cabin on Pigeon Lake, and for providing boat and vehicle storage at the Provincial Park warehouse. Human Resources and Development Canada provided partial funding to seasonal staff and The Fish’n’ Hole provided discounts on equipment. Also, I would like to acknowledge Dr. Michael Sullivan and Vance Buchwald of Alberta Fish and Wildlife and David Park (ACA) for reviewing and providing essential improvements to this report. iii LIST OF FIGURES Figure 1. Location of Pigeon Lake in central Alberta.. ..................................................... 3 Figure 2. A flow chart describing the mathematical operations used to estimate parameters from the sport fishery at Pigeon Lake 2003.. ....................... 7 Figure 3. A comparison of probability density function of the total number of anglers at Pigeon Lake, in 1999 and 2003.. ............................................................. 9 Figure 4. A comparison of the probability density function of the number of hours that anglers expended at Pigeon Lake in 1999 and 2003.. ...................... 9 Figure 5. A comparison of the probability density function of angling pressure at Pigeon Lake in 1999 and 2003................................................................... 10 Figure 6. A comparison of the probability density function of the number of released walleye by the sport fishery from Pigeon Lake in 1999 and 2003.. ..... 11 Figure 7. A comparison of the probability density function of the mean weight of walleye released by the sport fishery from Pigeon Lake in 1999 and 2003............................................................................................................... 11 Figure 8. A comparison of the probability density function of yield from incidental walleye harvest from Pigeon Lake in 1999 and 2003. ........................... 12 Figure 9. A comparison of the probability density function of the pike sport fishery harvest from Pigeon Lake in 1999 and 2003. .......................................... 13 Figure 10. A comparison of the probability density function of the mean weight of pike harvested by the sport fishery from Pigeon Lake, 2003............... 13 Figure 11. A comparison of the probability density function of the yield of pike harvested by the sport fishery from Pigeon Lake in 1999 and 2003.. 14 Figure 12. Distribution of age-classes and year-classes of 200 walleye sampled by the volunteer test fishery.. ............................................................................... 15 Figure 13. Age-class and year-class distribution of walleye sampled from the FWIN.16 Figure 14. A comparison of total catch rates of walleye derived from creel surveys conducted between 1990 and 2003 in Pigeon Lake. .............................. 16 Figure 15. Mean catch rates of walleye from FWIN (2000 to 2003). ............................... 17 v Figure 16. Length-at-age (logarithmic lines-of-best-fit) of walleye from the volunteer test fishery and the FWIN at Pigeon Lake, 2003. ................................... 18 Figure 17. Age-at-maturity of walleye as sampled by the FWIN, Pigeon Lake 2003... 19 Figure 18. Age-class distributions of sport harvested pike from Pigeon Lake, 2003.. 21 Figure 19. Length frequency distribution of sport harvested and test fishery sampled pike from Pigeon Lake, 2003..................................................................... 22 Figure 20. Length-at-age of sport harvested pike from Pigeon Lake, 1999 and 2003. 22 vi LIST OF TABLES Table 1. Observed, reported and estimated catch rates of anglers who initiated angling trips from the Provincial Park in 1999 and 2003, Pigeon Lake, Alberta. .......................................................................................................... 8 vii LIST OF APPENDICES Appendix 6.1 An example of a creel survey field data form...........................................27 Appendix 6.2 Percentages of angling effort from access points on Pigeon Lake. ........28 Appendix 6.3 Daily summary of angler survey data in Pigeon Lake, 2003. .................29 Appendix 6.4 Biological data of walleye captured by test fishing in Pigeon Lake, 2003................................................................................................................31 Appendix 6.5. Biological data from sport harvested pike from Pigeon Lake, 2003. .....37 Appendix 6.6. Biological data from pike captured as part of the test fishery in Pigeon Lake, 2003.....................................................................................................38 viii TABLE OF CONTENTS EXECUTIVE SUMMARY.............................................................................................. ii ACKNOWLEDGMENTS ............................................................................................